No problem at all.
I have that same processor running at stock speeds in an old rig paired with a 560ti which is just a little slower than the 7850. It seems to be a good pairing. The problem with those prebuilts (like mine was too) is that the motherboards don't allow overclocking to bring that Core 2 Quad up to more modern standards so we're pretty limited as far as what kind of a GPU we can toss in there.
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